Two-needle blindstitch sewing-machine.



w. ARBETTER.

TWO NEEDLE BLINDSTITQH SEWING MACHINE.

APPLICATION FILED JUNE 2. I908.

1,156,128. Patented 0a 12, 1915.

3 SHEETSSHEET 1.

J 9 are i 0 i U 3 asses:

W. ARBETTER.

TWO NEEDLE BLINDSTITCH SEWING MACHINE.

APPLICATION FILED JUNE 2, 19081 Patented Oct. 12, 1915.

3 SHEETSSHEEI' 2.

W. ARBETTER.

TWO NEEDLE BLINDSTITCH SEWING MACHINE.

APPLICATION FILED JUNE 2.1908.

Patented Oct. 12, 1915.

3 SHEETSSHEET 3.

UNITED STATES PATENT OFFICE.

. I WOLF ARBETTER, OF CHELSEA, MASSACHUSETTS, ASSIGNOR TO ARBETTER' FELLING MACHINE COMPANY, OF BOSTON, MASSACHUSETTS, ACORPORATION OF MAINE.

TWO-NEEDLE BLINDSTITCH SEWING-MACHII TE.

Application filed June 2,

To all whom it may concern:

Be it known that I, WOLF ARBnT'rER, a

sewing 'machine for uniting two or more layers of cloth by two rows of connected blind stitches, or stitches which enter and emerge from the same face of the material.

The mechanism of this invention employs tworeciprocating needles having their penetrating movements in alternation, each of which forms one of the rows of blind stitches.

The machine of this invention is particularly designed for what is known as padding work, wherein one or more upper layers of cloth are'united to alower or base layer. A very large amount of such work is done in the manufacture of garments where stiffening material is attached to the main fabric of the garment by numerous rows of blind stitches. The stitches so made are concealed from view by the lining which is subsequently applied, but it is necessary that this work shall be done thoroughly and well, and that a very large number of stitches shall be made in order to insure a well stiffened garment structure. It is also desirable that this work shall be done as rapidly as possible and for that reason speed in the making of the stitches is an important factor. V p i The present invention employs two needles reciprocating with their penetrating. movements in alternation to form the two rows of blind stitches which when connected form the seam. By using two needles it is obvious that the work can be done twice as fast as by the use of one needle because the work can be fed twice as rapidly, and the other parts of the machine timed accordingly.

The invention involves other features Specification of Letters Patent.

Patented Oct. a2, 1915. 190a. 'Serial1 1'o.43( 224.

While the invention is particularly designed tor use in the making of a padding seam, still with very slight alteration it can be used for felling work, or work wherein the edge, whether turned or raw, of a superimposed layer 01'' layers, united to a base layer. The invention will more fully appear from the accompanying description and drawings, and will be particularly pointed \outin the claims.

F The drawings illustrate the preferred form of the invention, but the form illustrated is butone specific construction in whicln the invention may be embodied, and it is obvious that the invention, especially in its broad features, is not restricted to this particular embodiment.

Figure 1 is a side elevation of the main portion of a machine embodying the invention. Fig. 2 is an end elevation of the construction shown in Fig. 1. Fig. 3 is a detail view looking at the end of the machine with parts removed to show the mechanism'for .operating the needles. Fig. 4 is a side elevation, partially incross-section, of the forward end of the machine with partsremoved to show the operation of the needles and the take-up. Fig. 5 is a cross-section on the line a2a: of Fig. 4. Fig. 6 is a diagrammatic view of the cam for operatingfthe needlebar. i

The work-supporting mechanism, the feeding mechanism and the mechanism .for operating the bender which projects the work into the path of the curved needles at the desired times, are each and all, except for certain particular features hereinafter I noted, constructed and arranged as shown in other blind stitching machines of my invention, and the particular construction especially adapted for use in connection with this invention and which is illustrated so far as necessary in the drawings herein, is also illustrated and described in detail 'in United States Patent No. 1,152,871, granted September 7, 1915, for blind-stitch felling machine.

The machine comprises the usual bedplate A and overhanging arm B. A verticall v-mm'able work-support A is mounted in said blll-Plflllt to coiiperate with the ad justable presser-foot I). mounted in the overhanging arm B. The work-support is held yieldingly upward against the Presser-foot and is depressed when desired by the knee lever A.

The feed-dog A is given the usual four motion feeding movement and has its upper surface properly shaped to cooperate with the two needles and the presser-foot.

'lhe bender mechanism for projecting the material into the path of the needles may be of any suitable form and operated in any suitable manner according to the character of the work done, but in the specific construction herein shown comprises a benderbar A provided at its upper endwith two benders A, A, one for each needle and each adjustably -mounted in the bender-bar by set-screws when the bar is moved upwardly at the required times to project the fabric into the path of the needles in the usual manner to enable the formation of the blind stitch.

In the preferred form of the invention the needles are of the curved eye-pointed type and receive their reciprocations from the oscillations of the shafts by which they are carried. Two concentrically-arranged needle-carrying rock-shafts are mounted in a depending projection B of the overhanging arm. One of these shafts B is shown as solid and carries at one end an. arm B in the end of which the curved needle N is clamped. T he other of these shafts B is tubular, and surrounds the shaft 13 and carries at its end a second arm B. in the end of which the curved needle N is clamped. The two needles, therefore, oscillate in parallel planes.

The needles are operated in the construction shown by a rack and pinion construction. Each shaft B 13 carries at its end opposite from the needles the pinions l8",

3", respectively. Each of these pinions has teeth through half of its circumference and presents a cylindrical surface throughout its other half. A rack-bar C slides vertically in ways C in the forward end of the arm, and is provided at its lower end with racks C", lying respectively in the planes of the pinions B and B The rack-bar also presents smooth surfaces opposite to the racks C and C which cooperate with the smooth surfaces respectively on the pinions B and B The forked lower end of the rack-bar C is split and provided with asetscrew {5 by means of which any lost motion between the racks and the pinions may be taken up. lit will thus be seen that when the pinions 1B" and B are properly adjusted on their respective shafts and the rack-bar C is reciprocated, that the needles 3% and N will reciprocate 01' oscillate with their penetrating movements in alternation.

The penetrating movement of the needle is herein to be understood to be that movement of the needle pointfirst which takes place when it is moved to enterand pass through the material and is to be contradistinguished from the retracting movement which takes place when the needle returns. T he reciprocating movementof the rack-bar C is secured means of a face-cam E, mounted on the.forward end of the main shaft F of the machine by means of a stud C carried on the rack-bar C and entering the groove E of the facecam.

lltis necessary that both of the needles should be entirely out of the fabric at the time each feeding action talresp'lace, which feeding action occurs after each stitch has been made. In the construction shown the required movement is secured by the cam E, and it is found that if one needle in its upward movement after withdrawing from the fabric and the other needle in its downward movement before entering the-t fabric, have their actions substantially suspended during of the revolution of the cam. that sufficient time is allowed for the feeding of the fabric at each stitch. The groove E in the cam E is therefore arranged as shown in Fig. 6, with the diametrically opposite sections of about 60 marked feeding', substantially concentric to the axis of the cam, so that substantiallv no movement is given to the needles at this time. The other sections of thecam are arranged symmetrically and in equal divisions and so shaped as to give the needles the proper reciprocations or oscillations, half of the reciprocation or oscillation of each needle taking place on each side of the feeding movement.

in order that the thread carried .by the needles may be properly controlled it is necessary that there should be a separate takeup device for each needle. timed to coiiperate with its particular needle. This is secured in the construction illustrated by providing two independently operating take-up levers (5. 1 'l he operation and consequently the oscillation of the take-up being the same in each case but in opposite phases, the take-up levers are shown as operated from the same take-up cam G To secure this result one take-up G is fast to a shaft G journaled in the arm of the machine. and is provided with a. rocker-arm (i having a stud G riding in the cam groove G of the cam at one side thereof, while the other take-up G is fast to a sleeve G", surrounding and journaled upon the shaft G and provided with a rocker-arm G, having a. stud G entering I the groove G" of :the' take-up cam at a point head of the machine and are thus moved in alternation to take-up the thread of their -respective needles. A cover-plate Gr fastened to the side of the machine'allows of access to the take-up parts.

The two'threads are supplied to the two needles from spools H, H, and each thread passes around a suitable tension device as J, J, and through a suitable pull-off device as K, K

The complemental stitch-forming mechanism may be of any suitable form, but it is preferably of the thread-carrying type by which a third thread is interlocked by the two threads carried by the needle. A suitable form of such mechanism is illustrated in Patent No. 830,699, granted September 11, 1906, and need not be described herein as its specific construction forms no part of the present invention. It comprises a suitable framework M, a revolving hook m, and contained bobbin and bobbin case rotating in a plane-transverse and oblique to the paths of reciprocation of the needles and transverse and oblique to the work-support. The revolving hook may be operated from the main driving shaft by means described in said patent.

In the said patent the single needle is operated in divergent paths, and hence intersects the path of the hook at two separated points. stitch-forming mechanism is well adapted, therefore, for use with needles arranged and operating as in the present invention. In the said patent the two points at which the paths of the needle intersect the path of the hook are considerably farther apart than the extreme width of the seam. Hence, when the needles are arranged substantially par-- allel, as in the present invention, the width of the seam may be increased considerably and still have the paths of the needles intersect the path of the l-ooper at points no farther apart than in the mechanism of the said patent. WVhen the width of the seam is the same as that made by the mechanism of the said patent the paths of the needles in the present case will intersect the path of the looper closer together than in the case of the mechanism of the said patent. This allows in the present invention of a wide range of width of seam and at the same time the proper cooperation of the needles with Y the looper.

To insure the symmetrical character of the seam and prevent. the points of the needles from striking their own threads, the needles may be adjusted so as to converge or diverge slightly from the strict parallel lines. This Such form of complemental' may be secured in any suitable manner but it will be found sufiicient to adjust the .needles very slightly rotarily in the needle arm B orB by means of the usual set-screw P, the needle arm at the end being split to form a clamp for the needle in the usual manner.

With the construction arranged as illus-.

trated herein at each revolution of the main driving shaft each needle makes one complete'reciprocation into and out of the fabric to form a complete stitch, the needles having their penetrating movements in alternation. The revolving hook making, as in the aforesaid patents, two revolutions to each revolution of the main driving shaft will thus cooperate at each of its revolutions with one or the other of the needles to make their respective stitches.

The feed operating shaft making two revolutions to one of the driving shaft causes two complete feeding movements, one of which occurs after each stitch made by one or the other" of the needles. The. bender mechanism being operated from the same shaft comes up at each stitch, and being promakes an idle or useless elevation of the' material at every other stitch, but this does no harm and renders unnecessary the general duplication of the bender mechanism for many kinds of work, although the bender v mechanism may do. This arrangement enables the machine to be run at a comparatively high speed, or to produce about twice as much work at the same speed as would be produced by a machine of the type having a single vibrating needle such as illustrated in the before-mentioned patents. In the present construction with the driving shaft running at the same speed as in a single needle machine the rack-bar and each of the two needles operated thereby will make the same number of reciprocations as it made by the single needle of the single needle machine. The rotary hook running at the same speed as in the case of the single needle machine cooperates with both needles. The two take-ups being operated from the one cam of the drix'ing shaft each run at the same speed as the take-up of the single needle machine. The feeding mechanism and the bender mechanism are, therefore, the only mechanisms whose speed is increased and in the case of the latter the increase in speed is simple for convenience, because every other reciprocation is an idle one. The doubling of the speed of the-feeding mechanism is therefore the onlyincrease in speed which is made necessary in order to do twice the amount of work with the same speed of the driving shaft as is done in the single needle machine.

As already stated, this machine is designed particnlarly for doing work such as padding work, wherein both needles pass through into the same superimposed layers and attach them together by blind stitches. The machine, however, may be used for doing a certain class of telling work. in this case an edge, turned in or raw. of one or more layers is attached to a base layer; When this kind at work is done the stitches made by one needle will enter on the folded edge, and catch into the base layer or not, as desired, while the stitches'formed by the other needle will enter the main layer only close up to the edge of the upper layer, and the thread from the rotary hook will concatenate the two rows of stitches together. When telling work of this character is being done it is usually desirable that the stitches lying in the upper layer shall not enter, or at most enter. slightly, the main layer, and hence the needle forming these stitches may be adjusted to move at a slighter distance above the work-support than the other needle, and the bender coiiperating therewith may be adjusted accordingly.

lihe phrase stitch-forming mechanism" when used in the claims is a broad term including the instrumentalities necessary to form the stitch, such as the needles, and the complemental mechanism, such as the looper, hook or other device, and it will be noted that this mechanism being located and operated at one side of the work-support enables the formation of a blind stitch.

Patent No. 89%,567, granted July 28, 1908 illustrates and describes seams such as made by the machine illustrated herein. 7

Having described my invention, what ll claim as new and desire to secure by Letters Patent, is:

1. A blind stitch sewing machine comprising a work support, two reciprocating needles located and operating side by side and at one side of the work support, means for reciprocating the said needles in alternation with their penetrating movements in the same direction, and stitch forming mechanism complemental to said needles located and operating at the same side of the work support as the needles.

2. A. blind stith sewing machine, comprising, a work support, stitch forming mechanism located and operating at one side of the work support, said stitch forming mechanism haeluding two needles reciprocatme ias ing in paths extending in the same general direction and having their penetrating movements in alternation and in the same direction.

3. A blind stitch sewing machine comprising a work support, and stitch-forming mechanism located and operating at one side of the work-support including two reciprocating needles having their penetrating movements in alternation, and a single cornplemental thread carrying stitch forming device coiiperating with both needles alternately.

4:. A blind stitch sewing machine comprising a work support, two oscillating curved needles located and operating side by side and at one side of the work support, means for oscillating the said needles in alternation with their penetrating movements in the same direction, and stitch-forming mechanim complemental to said needles located and operating at the same side of the work support as the needles.

5. A blind stitch sewing machine comprising a work-support and stitch-forming mechanism located and operating at one side of the work support including two oscillating curved needles having their penetrating movements in alternation, and a single complemental thread carrying stitch forming device coiiperating with both needles alternately.

d. A blind stitch sewing machine comprising a work-support, stitchiornnng mechanism located and operating at one side of the work-support including two reciprocating needles having their penetrating movements in alternation, a take-up cam prm'ided with a symmetrically-arranged groove, and two take-up levers one for each needle. provided with studs engaging diametrically opposite portions of said cam groove, whereby the take-up levers are actuated from a single cam in alternation to coiiperate with the said needles.

Z. A blind stitch sewing machine comprising a work-support, stitch-forming mechanism located and operating at one side of the work-support including two reciprocating needles having their penetrating movements in alternation. a take-up cam provided with a symmetrically-arranged groove. and two take-up levers one for each needle concentrically mounted and provided with studs engaging diametrically opposite portions of said cam groove, whereby the take-up levers are actuated from a single cam in alternation to coiinerate with the said needles.

8. A blind stitch sewing machine comprising a work-support stitch-forming mechanism located and operating at one side of the work-support, including two oscillating curved needles having their penetrating movements in alternation, and means for feeding the work over the work trically arranged needle carrying rock shafts, means for operating the same in .alternation, and a curved needle mounted on each of said rock-shafts.

11. A blind stitch sewing machine comprising a work-support, stitch-forming mechanism located and operating at one side of the work-support including two concentrically arranged needle carrying rock shafts, means for operating the same in alternation, and a curved needle mounted on each of said rock-shafts, a rotary threadcarr'ying complemental stitch-forming device cooperating with both of said needles alternately, and means for giving one rotation of the said device to each reciprocation of each needle.

12. A blind stitch sewing machine comprising a work-support, stitch-forming mechanism located and operating at one side of the work-support, including two oscillating curved needles having their penetrating movements in alternation, and a rotary hook and contained bobbin and bobbincase, and means for giving one complete rotation of said hook to each complete reciprocation of each needle.

13. A blind stitch sewing machine comprising a work-support, two concentricallyarranged needle carrying rock shafts mounted above said work-support, and each provided with a curved needle, a pinion mounted on each of said shafts near the end thereof, a rack-bar provided-with parallel racks one for each pinion, and means for reciprocating the said bar to cause the oscillation of the said needles with their pene trating movements in alternation.

14. A blind stitch sewing machine comprising a work-support, stitch-forming mechanism located 'and operating at one side of the work-support, including two reciprocating needles having their penetrating movements in alternation, a bender bar located beneath the work-support and provided with two benders, one for each needle, and means for reciprocating the said bender-bar 'at each reciprocation of each needle. g

15. A blind stitch sewing machine comprising a work-support, stitch-forming mechanism located and operating at one side of the work-support, including two oscillating curved needles, a reciprocating bar, and connections between the said bar and the said needles whereby upon each reciprocation of the bar the said needles are each given a complete oscillation with their penetrating movements in alternation.

16. A blind stitch sewing machine comprising a work-support, suitable feeding mechanism, stitch-formingmechanism located and operating at one side of the worksupport, including two oscillating curved needles, a reciprocating bar, and connections between the said bar and the said needles whereby upon each reciprocation of the bar the said needles are each given a complete oscillation with their penetrating move-- 

